Express your answer as a mixed number simplified to lowest terms. $19\dfrac{12}{20}+9\dfrac{4}{15} = {?}$
Explanation: Separate the whole numbers from the fractional parts: $= {19} + {\dfrac{12}{20}} + {9} + {\dfrac{4}{15}}$ Bring the whole numbers together and the fractions together: $= {19} + {9} + {\dfrac{12}{20}} + {\dfrac{4}{15}}$ Add the whole numbers: $=28 + {\dfrac{12}{20}} + {\dfrac{4}{15}}$ Simplify each fraction: $= 28 + {\dfrac{3}{5}} + {\dfrac{4}{15}}$ Find a common denominator for the fractions: $= 28+\dfrac{9}{15}+\dfrac{4}{15}$ Add the fractions: $= 28+\dfrac{13}{15}$ Combine the whole and fractional parts into a mixed number: $= 28\dfrac{13}{15}$